Consider the following standard electrode potentials
Ag+ + e- = Ag, Eo = 0.80 V
Mn2+ + 2e- = Mn, Eo = -1.18 V
for the standard cell
Mn|Mn2+(aq)||Ag+(aq)|Ag
Which of the following statements are true?
1. The cell voltage will be 1.98 V.
2. One half-cell reaction is Mn = Mn2+ + 2e-
.
3. The overall cell potential will decrease with
time.
A) 1 only
B) 2 only
C) 3 only
D) 1 and 2 only
E) 1, 2, and 3
Which of the following statements are true?
2018-05-30 3:45 pm
回答 (1)
2018-05-30 4:24 pm
1. true
E°(cell) = E°(red) - E°(ox) = (0.80) - (-1.18) V = 1.98 V
2. true
The reaction for the oxidation half-cell is: Mn → Mn²⁺ + 2e⁻
3. true
The overall equation for the cell is: 2Ag⁺(aq) + Mn(s) → Mn²⁺(aq) + Ag(s)
E° = E°(cell) - (RT/2F)ln([Mn²⁺]/[Ag⁺]²)
When reaction goes on, [Mn²⁺] is increasing while [Ag⁺] is decreasing, and thus [Mn²⁺]/[Ag⁺]² is increasing and -(RT/2F)ln([Mn²⁺]/[Ag⁺]²) is decreasing.
Therefore, the overall cell potential will decrease with time.
The answer: E) 1, 2 and 3
E°(cell) = E°(red) - E°(ox) = (0.80) - (-1.18) V = 1.98 V
2. true
The reaction for the oxidation half-cell is: Mn → Mn²⁺ + 2e⁻
3. true
The overall equation for the cell is: 2Ag⁺(aq) + Mn(s) → Mn²⁺(aq) + Ag(s)
E° = E°(cell) - (RT/2F)ln([Mn²⁺]/[Ag⁺]²)
When reaction goes on, [Mn²⁺] is increasing while [Ag⁺] is decreasing, and thus [Mn²⁺]/[Ag⁺]² is increasing and -(RT/2F)ln([Mn²⁺]/[Ag⁺]²) is decreasing.
Therefore, the overall cell potential will decrease with time.
The answer: E) 1, 2 and 3
收錄日期: 2021-05-01 22:26:57
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